A unit having the structure shown in FIG. 13(A) is known as a cap unit (a) for the above-mentioned tire puncture emergency repair apparatus, for example. This cap unit (a) is provided with a cap main body (c) comprising an opening-attaching concave part (c1) inserting and fixing an opening (b1) of a bottle container (b). The cap main body (c) comprises an air passage (e) to feed the compressed air from a compressor (d) through an air intake port (el) into a bottle container (b), and a sealing agents/compressed air extractive flow passage (f) to extract the puncture-sealing agent and the compressed air from the bottle container (b) to the tire T by feeding the compressed air.
A basal plane of the opening-attaching concave part (c1) is provided convexly with a column-shaped boss part (g); and an air flow passage upper opening (e2) forming an upper end of the above-mentioned airflow passage (e), and a sealing agent/compressed air extractive flow passage upper opening (f2) forming an upper end of the above-mentioned sealing agents/compressed air extractive flow passage (f) are opened on an upper end of this boss part (g). Incidentally, the air flow passage upper opening (e2) and the sealing agent/compressed air extractive flow passage upper opening (f2) are closed with an inner cap (i) connected with the above-mentioned boss part (g) so as to prevent an escape of the puncture-sealing agent.
Thus, at a time of puncture repairing, the compressed air is supplied to the air flow passage (e) by an actuation of the compressor (d). In this time, first of all, the inner cap (i) is automatically taken off from the boss part (g) by an increase of inside pressure; then, the compressed air inflows into the bottle container (b), and the puncture-sealing agent and the compressed air are injected in the tire T in succession, and the puncture emergency repair and a pump-up of the tire T are continuously conducted.
However, in the tire puncture emergency repair apparatus, while puncture repairing, there is a possibility of disconnection between the compressor (d) and the cap main body (c) because someone catches on the hose or drops the apparatus. In this case, there is a problem that the puncture-sealing agent inside the bottle container (b) belches from the air intake port (e1) and pollutes the surroundings because a high pressure (350 pKa, for example) is exerted in the bottle container (b).
However, the following Patent Document 1 makes a proposition to provide in the above-mentioned air flow passage (e) with a reversed flow preventing device (j) as shown in FIG. 13 (B). This reversed flow preventing device (j) prevents the remnant of the puncture-sealing agent collected inferiorly after repairing the puncture from leaking toward a compressor owing to its own weight. The reversed flow preventing device (j) is provided in a vertical air flow passage (ea) with a valve seat portion (j1) having a reduced diameter. The reversed flow preventing device (j) is provided above the valve seat portion j1 with a spherical valve j2, and in an air flow passage upper opening e2 with a secured pin j3 to prevent the spherical valve j2 from dropping.
In this structure, the secured pin j3 is connected with the air flow passage upper opening e2. Owing to the structure of shape forming mold, the vertical air flow passage (ea) has a diameter superiorly enlarging, and a joint with the secured pin j3 is likely to slack. Therefore, the compressed air from the compressor (d) makes it easier for the secured pin j3 to drop out and may cause the dropping of the spherical valve j2. Since the spherical valve j2 moves freely in the vertical airflow passage (ea), the valve function gets unstable; and when the puncture-sealing agent reversely flows at high pressure, the spherical valve j2 moves, and there is a difficulty of certainly preventing the reversed flow.    Patent Document 1: Japanese Unexamined Patent Application Publication No. 2010-023244.